I've downloaded Inkscape for 0.47-pre-4 and run it on Windows XP 32 bit. The newest feature I like so much is Stroke Shape for pencil tool which include the Ellipse shape. However, the default width of the shape is 1.00 unit which is equivalent to 10px. Since I want it to be 2px, I have to manually adjust it through Path Effect Editor. Unfortunately, I cannot find the way to make this path effect permanent to upcoming pencil. So, I've to adust the width of every single path and this is so annoying .

Are the any tips how to make the path effect permanent whenever I start to use pencil tool ?

I don't see something to help you. It would be good if it work when you had an ellipse that was 2 px high and copied it to the clipboard, and used "From clipboard" in the pencil tool. But I think it adjusts it to 10 px. You should put in a request on the launchpad site.

Thanks for the response.

I checked in Launchpad and it seems that someone has requested it. Here the number: https://bugs.launchpad.net/inkscape/+bug/295774.
So, I add my wish too...

Didn't see that one. Hopefully someday they'll implement, but don't expect it in 0.47.